Coastlines: at moderate flood stage, usually water overtops the natural dune and begins flooding coastal areas.Roads are likely to be closed and some areas cut off. Rivers: inundation of buildings usually begins at this stage.Lifeguard structures and beach concession stands will usually be flooded and may be damaged by surf. Coastlines: water will usually run all the way up to the dune in waves during a minor flood.Few, if any, buildings are expected to be inundated, however, roads may be covered with water, parklands, and lawns may be inundated and water may go under buildings on stilts or higher elevations. Rivers: minor flooding is expected at this level, slightly above flood stage.

Coastlines: at action stage, usually elevated tides and minor inundation of low-lying beach areas occurs.

Rivers: typically at this level, the water surface is generally near or slightly above the top of its banks, but no man-made structures are flooded typically any water overflowing is limited to small areas of parkland or marshland.

In the United States, there are five levels of flooding.

Many communities have inundation maps that provide information on which areas will flood at which stages. Current stage data is collected by the USGS using a network of gauges, over 9000 of which transmit real time data via satellite, radio, or telephone. In the United States during flood events, the National Weather Service will issue flood warnings that list the current and predicted stages for affected communities as well as the local flood stage. It can also be set for a specific location ('flood stage is 12 feet on Maple Street at First Avenue' means that the specified intersection will begin to flood when the stage reaches 12 feet (3.7В m)). The flood stage can be listed for an entire community, in which case it is often set to the lowest man-made structure or road in the area, the lowest farming field in the area, or the floodplain. Because flood stage is defined by impacts to people, as opposed to the natural topography of the area, flood stages are usually only calculated for bodies of water near communities. While usually the flood stage is set at the elevation of the floodplain, it can be higher (if there are no structures, roads, or farming areas immediately on the floodplain) or lower (if there are structures such as marinas, lake houses, or docks low on the banks or shores of the body of water) depending on the location. Levels below zero are reported as a negative value. The flood stage measurements are given as a height above or below the zero level. Stage was traditionally measured visually using a staff gauge, which is a fixed ruler marked in 1/100 and 1/10 foot intervals, however electronic sensors that transmit real-time information to the Internet are now used for many of these kinds of measurements. The zero level can be arbitrary, but it is usually close to the bottom of the stream or river or at the average level of standing bodies of water. 'Gauge height' (also referred to as 'stream stage', 'stage of the ', or simply 'stage') is the level of the water surface above an established zero datum at a given location. The term 'at flood stage' is commonly used to describe the point at which this occurs. Example graph of stream stages showing Action Stage, Flood Stage, Moderate Stage, Major Stage, and Record Stage on a river.ДЇlood stage is the water level, as read by a stream gauge or tide gauge, for a body of water at a particular location, measured from the level at which a body of water threatens lives, property, commerce, or travel.

Stone flood level 87